---
title: "CVE-2021-34833: Use After Free | CubePath"
description: "This vulnerability allows remote attackers to execute arbitrary code on affected installations of Foxit PDF Reader 11.0.0.49893. User interaction…"
language: en
source: https://cubepath.com/security/cve/CVE-2021-34833
---

# CVE-2021-34833: Use After Free | CubePath

## Description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Foxit PDF Reader 11.0.0.49893\. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the handling of Annotation objects. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-14023.

Official description from the CVE record, published by zdi. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-34833)

## Key data

### CVSS 3.0 High 7.8

Score published by zdi in the CVE record.

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

| Metric                 | Value     | What it means                                                                             |
| ---------------------- | --------- | ----------------------------------------------------------------------------------------- |
| Attack vector          | Local     | The attacker needs local access to the system, or to trick a user into running something. |
| Attack complexity      | Low       | No special conditions are needed. The attack can be repeated at will.                     |
| Privileges required    | None      | No account or privileges are needed.                                                      |
| User interaction       | Required  | A user has to do something first, such as opening a file or following a link.             |
| Scope                  | Unchanged | The impact stays within the vulnerable component.                                         |
| Confidentiality impact | High      | Serious or total effect on the secrecy of data.                                           |
| Integrity impact       | High      | Serious or total effect on the trustworthiness of data.                                   |
| Availability impact    | High      | Serious or total effect on availability.                                                  |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.95655 (95.7% probability)

Percentile

99.9%

Scores of

Nov 10, 2026

Model

v2026.06.15

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-416](https://cwe.mitre.org/data/definitions/416.html) Use After Free

## Affected products

Products listed in the CVE record, as the CNA published them.

- Foxit PDF Reader

  - affected: 11.0.0.49893

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [foxit.com/support/security-bulletins.html](https://www.foxit.com/support/security-bulletins.html)
- [zerodayinitiative.com/advisories/ZDI-21-915](https://www.zerodayinitiative.com/advisories/ZDI-21-915/)

## Timeline

1. ID reserved Jun 17, 2021
2. Record published Aug 4, 2021
3. Record last updated Aug 4, 2024

## Look up another CVE

## About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

[Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection)

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 20:02 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)